Greetings - New member with Tachometer question

[NT George]

I purchased a 2010 NT700V as a project bike and knew it needed a little TLC. I discovered the starter switch / headlight issue first.
Now I'm looking into an intermittent tachometer. It always cycles clockwise and back, like the speedometer, on power up. But it's either working, or not working, after I start the engine. So far it seems to work more in the garage sitting on the side stand. If I move the bike and put it up on the center stand it usually stops working. I purchased a Hayes manual and believe the tachometer is driven by the ECM module. But, the wiring diagram does not give any detail on the individual wires in the Instrument connector or the ECM connectors. Has anyone ever heard of this issue before and can give me some direction; or have a better wiring diagram which identifies which pin on either the Instrument or ECM connector controls the tachometer?
I'm getting ready to open it up and do a valve adjustment. Figure it would be a great time to check connectors and the wiring harness.
Thanks in advance.

 

[Phil Tarman]

Welcome to the Forum, George! I wish I could help you, but I can guarantee that someone the Forum will be able to.

What have you been riding before you got the NT? I've had two 2010s, both ABS bikes in silver. None of the red '10 models and some of the silver ones were non-ABS. They've both been good bikes for me.

 

[seagrass]

George before getting too carried away, just try unplugging and then reconnecting the wiring loom/s that connect to the instrument cluster.

It is very likely that the problem is an intermittent connection, probably in those connectors. Also check for corrosion in those connectors.

Seagrass

 

[Nick Wilkinson]

"...reconnecting the wiring loom..."

In addition, slap some dielectric grease into the connector. It keeps water and oxygen at bay. Every time I find a new connector, I will separate and rejoin it a few times then finally reconnect with the grease.

 

[ColoradoRod]

In addition to unplugging/plugging the connectors, it'd be worth spraying them with some contact cleaner. Wait for the cleaner to evaporate and then install some dielectric grease as mentioned above. Since the tach sometimes works, I'd guess a connector is your issue.

Amazon.com: DeoxIT 5% Spray Contact Cleaner, 5 oz.: Musical Instruments

Amazon.com: DeoxIT 5% Spray Contact Cleaner, 5 oz.: Musical Instruments

www.amazon.com

 

[NT George]

Welcome to the Forum, George! I wish I could help you, but I can guarantee that someone the Forum will be able to.

What have you been riding before you got the NT? I've had two 2010s, both ABS bikes in silver. None of the red '10 models and some of the silver ones were non-ABS. They've both been good bikes for me.

Hi Phil,
Way back when, when I was a young man, I started on a 1975 Hodaka Road Toad while stationed at Mountain Home AFB. Used it mostly for on base and off road adventures. After my discharge in 1980, with a young family and the purchase of a home, I just couldn't afford to pursue it and figured the Western NY drivers would run me over.
After the family was grown I started to get the bug again. But, was still a little uneasy about the cars on the road. In 2005/2006 I inherited and restored a 1975 Honda CB550. Figured I try this on road stuff and see what it was like. In 2006 I enjoyed the riding more than the repairing and traded it in on a new 2006 Kawasaki Concours at the end of that season. Three years later I started looking for a more comfortable long distance ride and purchased a used 2000 GL1500SE Goldwing. The wife started riding with me and we joined GWRRA. Another 3 years passed and in 2012 I purchased a used 2005 Goldwing. My 2015 retirement gift, from me to me with love, was a 2013 Goldwing with everything but the air bag, which we soon had converted with a Roadsmith trike kit. I sold the 2005 to a friend several years ago, still have the trike and occasionally miss 2 wheels. The NT700 checked all the squares on paper - smaller, lighter, more economical and shaft drive. After 2 silver bikes and 2 silver cars I bought a red NT700. I'm digesting the manual and becoming familiar with the NT. If nothing else it will be a learning experience.
Thank-you to all who responded.

 

[Phil Tarman]

George, I think you'll like the NT!

 

[Brillot2000]

Welcome Aborad and Greetings from SoCal.

Regarding the gauges issue. You will most likely need to remove all or most of the bodywork to gain access to the back of the instrument cluster. Disconnect the connector behind the meter assembly. Spray both the connector and the housing with an Electrical Contact Cleaner. Plugin and remove the connector several times to remove the contact oxidation. Remove the connector one last time. Then coat the connector housing where the contact pins with plenty of Dielectric Grease. Insert the connector back into the meter assembly. Then verify that everything is work and put everything back together. You should not have this issue for many years to come.

Honda CB550, huh? That was #2 on the worst bikes I ever owned. What Was The Worst Motorcycle You Ever Owned?

 

[NT George]

Welcome Aborad and Greetings from SoCal.

Regarding the gauges issue. You will most likely need to remove all or most of the bodywork to gain access to the back of the instrument cluster. Disconnect the connector behind the meter assembly. Spray both the connector and the housing with an Electrical Contact Cleaner. Plugin and remove the connector several times to remove the contact oxidation. Remove the connector one last time. Then coat the connector housing where the contact pins with plenty of Dielectric Grease. Insert the connector back into the meter assembly. Then verify that everything is work and put everything back together. You should not have this issue for many years to come.

Honda CB550, huh? That was #2 on the worst bikes I ever owned. What Was The Worst Motorcycle You Ever Owned?

Thanks Brillot2000. The CB550 served me well for the whole 4 months I had it on the road. After cleaning the carbs to get it running, new tires/tubes and a lot of elbow grease, my biggest issue was making new holes in the mufflers and having to patch them. I can't say I've had any bad bikes. The CB550 had most of it's challenges due to age, rust and neglect. While the chrome was starting to pit and the inside of the mufflers were rusty, it looked pretty good from 20 feet away.
However, for a couple of days I was starting to think this NT could be a contender. But, I'm enjoying the challenge.


I found it! After several days of research and troubleshooting I finally figured it out.

The tachometer signal comes from the ECM module’s gray connector pin 17 to the instrument connector pin 9 (Yellow/Green wire). Along the way it goes through the White connector at the end of the main wiring harness (adjacent to a blue connector) and both are connected to the front sub-harness and covered with a rubber boot.

Once I figured out the wiring diagram, I ohms checked the tachometer line from the ECM to the instrument connector – it checked good. Figured the problem had to be in the ECM or Instrument cluster. As I did not have a Peak Voltage Adapter, I used an oscilloscope and measured pin 9 at the instrument connector – it had a decent pulse square wave that varied with RPM. That pointed me towards the instrument cluster. I gently took it apart and found no signs of water or corrosion. While in there I decided to reflow any solder connections I could trace directly related to pin 9 or the tachometer meter. I put everything back together and sure enough – it still didn’t work. However, while it was disassembled I cleaned the plastic cover (inside & out) and now the instrument panel looks great…

As the ECM appeared to be working and the instrument panel looked good, I decided to take another look at the wiring before putting the bike back together. I fired it up and started wiggling the wire harness at the ECM and working my way forward. About the time I got up under the left pocket area it started working intermittently again. A closer examination of that white connector revealed the following – the male pin was fine but the opposing female portion had no tension and did not grip the male pin. And that was my intermittent contact problem. As I couldn’t figure out how to repair the female side, I circumvented the problem with a bypass wire. I also put connectors on the bypass wire so it can be separated if necessary.

The valve adjustments are fine, the tachometer is rock solid and what I initially thought was a possible brake line leak now looks like a left front fork seal. I haven’t done those before, maybe that will be my next project on this project bike.

Thanks for all the recommendations. While I didn’t find corrosion, it was a connector issue.

 

[ColoradoRod]

@NT George ... after reading your analysis, conclusion, and repair post, above, I feel like I owe you an apology for the simplicity of my post. By the look of your post, you obviously know WAAAAY more about electrical stuff than I could hope to know. My suggestion of contact cleaner and dielectric grease is on par with telling a 5-star Michelin chef to try adding salt! Lots of really smart people in this world!

 

[Brillot2000]

what I initially thought was a possible brake line leak now looks like a left front fork seal. I haven’t done those before, maybe that will be my next project on this project bike.

Thanks for all the recommendations.

When you are ready to approach the rebuilding of the forks. You might want to look over my thread on this subject. Fork Rebuilding - Brillot2000

I do not know your tool situation, however, it seems that you have quite a few to choose from. Be advised that I found having many of the tools called out in my thread were essential to do this job with some level of ease. I decided to use 15W fork oil over the recommended 10W. I find my bike performs better and with this simple change.

Having an impact driver with an impact-rated hex bit helped a lot with getting the securing screw out at the bottom of the fork housing. I also recommend that you leave the fork tubes clamped in place when doing this task. I also recommend purchasing all the items called out in my thread, better to be prepared when you get everything apart. I rebuild my forks over the weekend at a leisurely pace.

Good luck with your project.

 

[ARKNT]

Sounds like you did good on your tach issue. Things like an intermittent connector can be tough to find and/or fix.

Brad

 

[Brillot2000]

Sounds like you did good on your tach issue. Things like an intermittent connector can be tough to find and/or fix.

Brad

As the old saying goes, “Only as good as the weakest link.” This is more than true with electrical connections.

It’s really a process of elimination. Checking all electrical connections through the entire circuit is a part of good electrical troubleshooting skills.